The present invention relates to the field of controlling lighting functions in a vehicle.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
Modern vehicles have driver assist systems to alert the driver when, e.g., the driver has not buckled up or when the fuel tank is on reserve. More sophisticated systems can warn the driver about a danger condition near the vehicle and can involve an acoustic signal or a warning light in the event of, e.g., a pedestrian walking in a dark street.
To date, driver assist systems are developed to further provide comfortable driving conditions for the driver. For example, there are systems which recognize not only that the surroundings are dark but also that the vehicle negotiates a curve at a certain speed so that the light cone of the light is adjusted by the driver assist system, i.e. the light cone on the left side of the vehicle is for example enlarged to better illuminate the curb. This requires however that the driver has switched on the low beam, for example when the driver selects the function “Auto”, which means that the low beam is switched on or off depending on the ambient environmental conditions. This may be realized using e.g. a rotary light switch having a rotary knob to alternate between the various modes.
FIG. 1 shows an exemplary rotary light switch having various lighting functions. Reference numeral 1 indicates “Light Off”, reference numeral 2 indicates “Auto”, reference numeral 3 indicates “Parking Light”, reference numeral 4 indicates “Low Beam”, and reference numerals 5 or 6 indicate in combination with low beam 4 the mode “Low Beam +Fog lamp”. Such a rotary light switch may be integrated in a module 7, as shown by way of example in FIG. 1 or may be attached to the steering wheel. Operation of such a rotary light switch in a conventional manner is problematic in certain circumstances. For example, when the setting “Auto” is selected and the low beam is activated, there may be circumstances that require the driver during travel at night or because of other conditions to switch on the fog lamps. For that purpose, the rotary light switch has to be switched from the position “Auto” to the position “low beam +fog lamp”, i.e. the driver has to turn the rotary light switch from the position 2 “Auto” past the position 3 “Parking Light” to the position 4 “low beam”. The rotary knob 9 of the rotary light switch is then pulled out and moved to either the position 5 or 6. The arrangement or sequence of the lighting functions as shown in FIG. 1 is required by law so that activation of the low beam is always preceded by activation of the parking light. As a result, a switching from “Auto” to “Low Beam” or “Low Beam +Fog lamp” involves also activation of the parking light so that for a certain time period the bright low beam is replaced by a substantially darker parking light. Regardless how brief this time period is, this situation involves risk.
It would therefore be desirable and advantageous to address this problem and to obviate other prior art shortcomings.